1. Field of the Invention
The present invention relates to a graphic data processing apparatus which is capable of generating drawings, figures, and any other geometric, graphical or pictorial visible patterns or representations, and which has a function of assessing the patterns or representations for adequacy and correcting, improving, modifying or otherwise changing the design of the patterns or representations.
2. Discussion of the Prior Art
There is known a graphic data processing apparatus including graphic data processing means adapted to generate a visible pattern such as a drawing, which is defined by points represented by graphic data entered through an input device, and lines connecting the points. The graphic data processing apparatus further includes a display for displaying the points and lines, and the visible pattern defined or formed by these points and lines. For example, the graphic data processing apparatus is used for a computer-aided design (CAD) system adapted to produce design drawings. The use of such graphic data processing apparatus permits more efficient and accurate generation of patterns or drawings, as compared with a manual drawing using pencils, pens or other drawing instruments. Design data representative of such patterns or drawings generated by the graphic data processing apparatus are stored in a memory, with appropriate identification codes or labels, so that the corresponding patterns or drawings may be displayed on the display, drawn or plotted on a paper, or otherwise reproduced, by entering the appropriate identification codes or labels.
Usually, the graphic data processing apparatus of the type indicated above has a function of providing operating or guidance instructions on its display screen, for informing or advising the user of the functions available on the apparatus or the operating procedure. The instructions enable the user to easily operate the apparatus without a prior thorough knowledge on the apparatus, allowing the user to produce with high efficiency and precision desired drawings or other visible patterns which consist of known segments such as straight lines or circular arcs.
Although the graphic data processing apparatus assures relatively easy and accurate generation of desired patterns, there are some problems with the generated patterns, in terms of the function, ease of manufacture, production efficiency and economy and so forth, of an article or member which is represented by the patterns such as design drawings. Namely, the drawings generated by the apparatus cannot be embodied or reduced to practice as contemplated, or do not produce a desired result or does not meet a desired object. In the field of designing machinery using such graphic data processing apparatus, for instance, a component or part of a machine whose design drawing is generated by the apparatus must satisfy various requirements or conditions such as mechanical strength, dimensional accuracy, fit quality or tolerance, stress concentration limit, type and manner of welding, and type of machining, as considered in connection with the other components or parts of the machine. On the other hand, the user of the apparatus who is not sufficiently experienced or skilled in the art as a designer or production engineer may manipulate the apparatus without full considerations of the above-indicated requirements or with inadequate or false judgement or determination relating to those requirements, resulting in defects or flaws in the design as represented or expressed by the generated drawings or patterns.